Pluto has no rings — New Horizons triple-checked. An exhaustive search for rings and dust particles around the dwarf planet before, during and after the spacecraft flew past Pluto in 2015 has come up empty.

“It’s a very long paper to say we didn’t find anything,” says team member Tod Lauer of the analysis, posted online September 23 at arXiv.org. But the nonresult could help scientists...

Weight from massive deposits of frozen nitrogen, methane and carbon monoxide, built up billions of years ago, could have carved out the left half of the dwarf planet’s heart-shaped landscape, researchers report online November 30 in Nature.

The roughly 1,000-kilometer-wide frozen basin dubbed Sputnik Planitia was on display when the New...

PASADENA, Calif. — The forecast on Pluto is clear with less than a 1 percent chance of clouds. Images from the New Horizons spacecraft show hints of what could be a few isolated clouds scattered around the dwarf planet, the first seen in otherwise clear skies.

Seven cloud candidates appear to hug the ground in images taken shortly after the probe buzzed by the planet in July 2015. Along...

A salty ocean more than 100 kilometers deep might lurk beneath Pluto’s icy heart, a new study suggests. The buried reservoir could have helped tip the dwarf planet over at some point in its past, bringing the heart-shaped region in line with gravitational forces from Charon, Pluto’s largest moon.

A subsurface ocean isn’t a new idea; researchers proposed the possibility in March to...

The ruddy north pole of Charon, the largest moon of Pluto, is probably a stain from Pluto itself, researchers report online September 14 in Nature. Methane gas wafting from Pluto’s surface sticks to the frigid pole during the moon’s decades-long winter; ultraviolet light from the sun then transforms the methane into reddish organic goop known as tholins.

The ruddy north pole on Charon, the largest moon of Pluto, is probably a stain from Pluto itself, researchers report online September 14 in Nature. Methane gas wafting from Pluto’s surface sticks to the frigid pole during the moon’s decades-long winter; ultraviolet light from the sun then transforms the methane into reddish organic goop known as tholins.

It has been eight months since the New Horizons spacecraft flew past Pluto (SN Online: 7/15/15), but the discoveries keep trickling in. Mission scientists have now recapped the latest findings in five papers published online March 17 in Science. Science News has previously reported on many of these findings, but to mark those months of discovery, here are nine newsy nuggets about our favorite...

Over the ground lies a mantle of white — on Pluto. Snow-capped peaks on the dwarf planet dot an otherwise ruddy terrain. But these snowy summits appear to be composed of methane, not water, researchers report online March 3.

Mountain tops in Pluto’s Cthulhu Regio, a dark landscape abutting the planet’s famous heart, reflect more light than the surrounding area. The New Horizons...

Pluto’s largest moon Charon is busting at the seams, and an ancient subsurface ocean might be to blame.

Ridges and valleys more than 6 kilometers deep, seen during the July 14 flyby of the New Horizons spacecraft (SN: 12/26/15, p. 16), suggest that the moon swelled at some point in its past. The rifts could have been carved by an ocean that froze and expanded, tearing apart the satellite...

Mountains of water ice tower thousands of meters over fields of frozen nitrogen and methane. Glaciers etched with channels hint at heat bubbling up from below. A patchwork of new and old terrains — some laid down in the last 10 million years, some as old as the planet itself — blanket the ground. And what appear to be two ice volcanoes punch through the terrain.